The invention relates to an oven for frying food products in hot oil, comprising a tank in which the frying oil can be accommodated, a gas-fired heating device connected to a heat exchanger which is situated in the tank and through which the smoke gases flow, and also an outlet for the smoke gases emerging from the heat exchanger. Such ovens are used for factory production of food products such as schnitzels, pre-fried chips, etc. They generally have a conveyor belt through which the frying oil can pass and by means of which the food products are conveyed continuously through the hot frying oil.
A heat exchanger, comprising a number of heat exchange pipes, is provided in the tank in order to heat the frying oil. These pipes preferably extend over as large a part of the tank as possible, in order to heat the oil uniformly in this way. Nevertheless, the part of each heating pipe closest to the heating device has a relatively high temperature. Particularly if the inner wall of this part of the heating pipes is directly exposed to the gas flame supplied by the heating device, there is a risk of the oil film on the pipes becoming too hot. The oil is cracked as a result, so that harmful products are formed. It will be clear that the formation of such harmful products is unacceptable.
The remaining greater part of the heat exchange pipes obtains its heat from the smoke gases flowing through it. However, the temperature of the smoke gases has already fallen greatly, particularly near the end of the pipes, which adversely affects uniform heating of the oil in the tank.